The psychological impact of diagnostic food challenges to confirm the resolution of peanut or tree nut allergy.

Background: Twenty percent of children outgrow peanut allergy and 10% outgrow tree nut allergy. Resolution can be confirmed by a food challenge. Little is known about the psychosocial impact of the challenge.

Highly accurate prediction of food challenge outcome using routinely available clinical data.

Background: Serum specific IgE or skin prick tests are less useful at levels below accepted decision points.

Objectives: We sought to develop and validate a model to predict food challenge outcome by using routinely collected data in a diverse sample of children considered suitable for food challenge.

Methods: The proto-algorithm was generated by using a limited data set from 1 service (phase 1).

Vitamin D3 supplementation for 16 weeks improves flow-mediated dilation in overweight African-American adults.

Background: A growing body of evidence has linked vitamin D deficiency to increased risk of cardiovascular disease. Vitamin D deficiency is also more common in African Americans for whom an increased cardiovascular disease risk exists. This study sought to test the hypothesis that 16 weeks of 60,000 IU monthly supplementation of oral vitamin D(3) would improve flow-mediated dilation (FMD) in African Americans, whereas no change would be observed in the placebo group.

Leukocyte telomere length in healthy Caucasian and African-American adolescents: relationships with race, sex, adiposity, adipokines, and physical activity.

Objective: To examine the relationships of race, sex, adiposity, adipokines, and physical activity to telomere length in adolescents.

Study Design: Leukocyte telomere length (T/S ratio) was assessed cross-sectionally in 667 adolescents (aged 14-18 years; 48% African-Americans; 51% girls) using a quantitative polymerase chain reaction method. Generalized estimating equations analyses were performed.

A 16-week randomized clinical trial of 2000 international units daily vitamin D3 supplementation in black youth: 25-hydroxyvitamin D, adiposity, and arterial stiffness.

Context: Vitamin D insufficiency/deficiency is commonly observed in black youth.

Objective: The aim was to determine 25-hydroxyvitamin D [25(OH)D] in response to 2000 IU vitamin D supplementation over time; to evaluate the relation between 25(OH)D concentrations and total body fat mass by dual-energy x-ray absorptiometry; and to determine whether vitamin D supplementation improves arterial stiffness measured by pulse wave velocity (PWV).

Design: We conducted a randomized, blinded, controlled clinical trial.

Low 25-hydroxyvitamin D levels in adolescents: race, season, adiposity, physical activity, and fitness.

Objectives: The objectives were to characterize the vitamin D status of black and white adolescents residing in the southeastern United States (latitude: approximately 33 degrees N) and to investigate relationships with adiposity.

Methods: Plasma 25-hydroxyvitamin D levels were measured with liquid chromatography-tandem mass spectroscopy for 559 adolescents 14 to 18 years of age (45% black and 49% female). Fat tissues, physical activity, and cardiovascular fitness also were measured.

The effect of a preoperative education programme on perioperative anxiety in children: an observational study.

The distress of children at the induction of anesthesia (DAI) is unpleasant for all involved and potentially harmful. Many strategies such as premedication or parental presence at induction have been described to minimize it. A preoperative education programme [the 'Saturday Morning Club' or (SMC)] has been in existence in our institution for a number of years and an observational study of children undergoing day case surgery was undertaken to assess the influence of attendance at the SMC on DAI.

Surfactant replacement for ventilator-associated pneumonia: a preliminary report.

Background: Surfactant abnormalities have been described in bacterial pneumonia.

Objective: To determine the safety and effect of exogenous surfactant replacement in patients with ventilator-associated pneumonia (VAP).

Methods: Patients with VAP were randomized in a double-blind study to receive either an artificial surfactant (Exosurf) consisting mostly of disaturated phospholipids (DSPL) or saline via a continuous nebulizer system for 5 days.

Regulation of epithelial Na(+) channels by actin in planar lipid bilayers and in the Xenopus oocyte expression system.

The hypothesis that actin interactions account for the signature biophysical properties of cloned epithelial Na(+) channels (ENaC) (conductance, ion selectivity, and long mean open and closed times) was tested using planar lipid bilayer reconstitution and patch clamp techniques. We found the following. 1) In bilayers, actin produced a more than 2-fold decrease in single channel conductance, a 5-fold increase in Na(+) versus K(+) permselectivity, and a substantial increase in mean open and closed times of wild-type alphabetagamma-rENaC but had no effect on a mutant form of rENaC in which the majority of the C terminus of the alpha subunit was deleted (alpha(R613X)betagamma-rENaC).

Malignant human gliomas express an amiloride-sensitive Na+ conductance.

Human astrocytoma cells were studied using whole cell patch-clamp recording. An inward, amiloride-sensitive Na+ current was identified in four continuous cell lines originally derived from human glioblastoma cells (CH235, CRT, SKMG-1, and U251-MG) and in three primary cultures of cells obtained from glioblastoma multiforme tumors (up to 4 passages). In addition, cells freshly isolated from a resected medulloblastoma tumor displayed this same characteristic inward current.

Ultrastructural localization of amiloride-sensitive sodium channels and Na+,K(+)-ATPase in the rat's olfactory epithelial surface.

Several studies have indicated that olfactory responses are impeded by amiloride. Therefore, it was of interest to see whether, and if so which, olfactory epithelial cellular compartments have amiloride-sensitive structures. Using ultrastructural methods that involved rapid freezing, freeze-substitution and low temperature embedding of olfactory epithelia, this study shows that, in the rat, this tissue is immunoreactive to antibodies against amiloride sensitive Na(+)-channels.

Use of bronchoalveolar lavage semiquantitative cultures in cystic fibrosis.

To assess bronchoalveolar lavage (BAL) in adult CF patients with respiratory symptoms, we studied BAL fluid (BALF) culture results from 28 bronchoscopies in 11 patients. Patients were asked to provide sputum for culture. All but two patients were receiving antibiotics at the time of bronchoscopy, with 13 bronchoscopies done on patients who had been receiving antibiotics for more than 10 d.

Protein kinase A phosphorylation and G protein regulation of type II pneumocyte Na+ channels in lipid bilayers.

Protein kinase A (PKA)- and G protein-mediated regulation of immunopurified adult rabbit alveolar epithelial type II (ATII) cell proteins that exhibit amiloride-sensitive Na+ channel activity was studied in planar lipid bilayers and freshly isolated ATII cells. Addition of the catalytic subunit of PKA + ATP increased single channel open probability from 0.42 +/- 0.

Changes in the inflammatory response of the lung during acute respiratory distress syndrome: prognostic indicators.

We studied paired bronchoalveolar lavage (BAL) in patients with sepsis-associated acute respiratory distress syndrome (ARDS). Patients were evaluated at one institution and underwent bronchoscopy with BAL within 48 h of the onset of ARDS. Patients were restudied with bronchoscopy and BAL after 4 d of treatment.

G-protein regulation of outwardly rectified epithelial chloride channels incorporated into planar bilayer membranes.

Experiments were designed to test if immunopurified outwardly rectified chloride channels (ORCCs) and the cystic fibrosis transmembrane conductance regulator (CFTR) incorporated into planar lipid bilayers are regulated by G-proteins. pertussis toxin (PTX) (100 ng/ml) + NAD (1 mM) + ATP (1 mM) treatment of ORCC and CFTR in bilayers resulted in a 2-fold increase in single channel open probability (Po) of ORCC but not of CFTR. Neither PTX, NAD, nor ATP alone affected the biophysical properties of either channel.

Relationship between visual sensitivity and target localization in older adults.

Older adults commonly report problems in visual search tasks and experience a higher incidence of mobility problems (e.g. falls and vehicle crashes), which involve visual skills.

Phosphorylation and activation of a bovine tracheal anion channel by Ca2+/calmodulin-dependent protein kinase II.

Secretion of Cl- by epithelial cells is fundamental to the processes of fluid and electrolyte transport by epithelia such as those of the airways, sweat-ducts, and gastrointestinal tract. In the present study, we show that a novel Cl- channel protein, immunoaffinity purified from bovine tracheal apical membrane vesicles, is sensitive to phosphorylation by Ca2+/calmodulin protein kinase II (CaMK II). The channel protein, which migrates with an M(r) of 140,000 under nonreducing conditions, is phosphorylated in vitro by CaMK II in a Ca(2+)- and calmodulin-dependent manner.

Regulation by phosphorylation of purified epithelial Na+ channels in planar lipid bilayers.

To determine the mechanism by which vasopressin increases apical membrane Na+ entry, we evaluated whether or not this hormone could recruit Na+ channels from a subapical membrane pool using specific polyclonal antibodies raised against high amiloride affinity bovine renal papillary Na+ channels. We also studied the effect of protein kinase A (PKA)-mediated phosphorylation on single-channel activity of highly purified Na+ channels incorporated into planar lipid bilayer membranes. PKA induced a significant increase in open-channel probability (Po) with no change in single-channel conductance.

Antibodies against purified epithelial sodium channel protein from bovine renal papilla.

Monoclonal and polyclonal antibodies against amiloride-sensitive sodium channel protein purified from bovine renal papilla have been produced. These antibodies show considerable specificity in enzyme-linked immunosorbent assay (ELISA) and dot-blot assays and can immunoprecipitate radiolabeled channel protein. The polyclonal antibodies bind two sodium channel subunits on Western blots, namely, the 300- and 110-kDa polypeptides, and cross react with channel protein isolated from the amphibian A6 renal epithelial cell line.

Jaundice in severe bacterial infection.

Thirty patients are described who developed jaundice during the course of severe bacterial infection. Although the infecting organism was variable, as was the site of infection, the patients were generally ill and pyrexial. The group had a very high mortality rate (43%).